Circuit breaker segrgation system



L. W. JACOBS CIRCUIT BREAKER SEGREGATION SYSTEM Oct. 1, 1968 2 Sheets-Sheet 1 Filed June 23, 1967 WMCM EMW. r v r Wu 4 w a Oct. 1, 1968 L. w. JACOBS 3,404,316

CIRCUIT BREAKER SEGREGATION SYSTEM Filed June 25, 1967 2 Sheets-Sheet z FIG. 7

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United States Patent CIRCUIT BREAKER SEGREGATION SYSTEM Lewis W. Jacobs, Garden City, N.Y., assignor to General Electric Company, a corporation of New York Filed June 23, 1967, Ser. No. 648,451 4 Claims. (Cl. 317-119) ABSTRACT OF THE DISCLOSURE A circuit breaker panel board having contacts which permit the engagement of certain types of circuit breakers, but prevent the engagement of other types of circuit breakers. Outwardly extending, blade-like contacts are provided which have slight protrusions on the upper edge. Circuit breakers including contact engaging clips which have a small notch are rejected from engagement because an edge of the clip abuts the protrusion on the contact. However, circuit breakers including a clip having a substantial cut-away portion so that the protrusion does not abut the clip easily engage the contact. Also, circuit breakers having either type of clip can engage contacts which do not have any protrusions thereon.

Background of the invention Circuit breaker panel boards are generally able to receive circuit breakers of a variety of amperage ratings, the desirability of the use of any circuit breaker of a given rating being dictated by the requirement of the device to be protected. Generally it is desirable when using circuit breakers of the plug-in type to restrict the use of circuit breakers of certain ratings in a panel board. For example, a circuit breaker of a given rating may be initially used in connection with a certain device to provide adequate protection therefor. However, if the circuit breaker is frequently tripping due to a current of the load it may be attempted to replace the circuit breaker with one of a higher rating. Such a replacement may be dangerous, in that in defeating the protective purpose of the circuit breaker a fire or destruction of the device might result. Therefore, by providing a physical interference prohibiting the engagement of the circuit breaker having the higher rating in the panel, such a dangerous situation may be prevented.

Summary of the invention Accordingly, it is an object of the present invention to provide a circuit breaker panel board having contact members which prohibit engagement therewith of certain types of circuit breakers, while allowing engagement of certain other types of circuit breakers.

The object of my invention may be realized by providing substantially rectangular contact members having offset protrusions thereon. Circuit breakers having one type of notched socket clips are rejected by the contact, as a part of the notch in the clip will abut with the protrusion so as to prohibit insertion of the clip onto the contact. However, circuit breakers having a second type of notched socket clip are accepted by the contact, as the clip is cut away so as to eliminate contact between the protrusion and the notched part of the clip to allow engagement of the clip on the body of the contact.

The specification concludes with claims particularly pointing out and distinctly claiming the subject matter which I regard as my invention.

Brief description of the drawings The embodiment of my invention is described in detail in the following description taken in connection with the accompanying drawings in which:

FIGURE 1A is a front elevation view of a circuit breaker panel board incorporating my invention, the front cover thereof being partially broken away;

FIGURE 1B is a fragmentary side view of the hook-on engagement of a circuit breaker onto the panel board;

FIGURE 2 is a fragmentary perspective view showing .a segregating contact;

FIGURE 3 is a perspective view of a first type of circuit breaker socket clip;

' FIGURE 4 is a fragmentary perspective view ofa circuit breaker having the first type of clip engaging the contact shown in FIGURE 2;

FIGURE 5 is a perspective view of a second type of socket clip;

FIGURE 6 is a fragmentary perspective view of a circuit breaker having the second type of clip being rejected by the contact shown in FIGURE 2;

FIGURE 7 is a fragmentary perspective view showing a universal contact;

FIGURE 8 is a fragmentary perspective view of a circuit breaker having the first type of clip engaging the contact shown in FIGURE 7; and

FIGURE 9 is a fragmentary perspective view of a circuit breaker having the second type of clip engaging the contact shown in FIGURE 7.

Description of the preferred embodiment FIGURE 1A shows my invention as incorporated in a circuit breaker panel board including an outer enclosure 2 having a front cover plate 4 retained thereon by suitable means such as screws 6. Also included is a circuit breaker supporting pan 8 resiliently supported by arcuate strip springs 10. The pan 8 serves to suport a suitable bus bar assembly. The bus bar assembly includes a body of insulating material 12 having imbedded therein three elongated and generally parallel bus bars 14, 16, 18. The bus bars have portions thereof projecting from the insulating body at one end and carrying line connecting terminals 20, 22 and 24, respectively. Each of the bus bars 14, 16, 18 has attached thereto along its length one or more blade-type contacts 26, which may include both segregating type contacts 26a and universal type contacts 26b. All of the contacts 26 are arranged in substantial alignment generally centrally of the insulating body 12, above the central bus bar 16.

The panel board further includes a number of electric circuit breakers 28, the casing of each of which has a recess 29 adapted to make a hook-0n type of engagement onto the supporting pan 8 by engagement with retaining hooks 30. A corner of each of the circuit breakers 28, opposite from the corner engaged under the hooks 30, is provided with a blade-receiving socket clip 32 in a suitable conforming recess within the insulating casing of the circuit breaker 28. A circuit breaker panel board of the general type described is shown and described in prior Patent 2,738,445, Hammerly et al., issued Mar. 13, 1956, and assigned to the same assignee as the present invention.

FIGURE 2 shows a close up view of the segregating contact 26a shown in FIGURE 1. The contact 26a may be of substantially rectangular shape and extends perpen dicular to the insulating bed 12. One of the bus bars, such as 16, is embedded within the insulating material 12 and is electrically connected to the contacts 26a. Two oppositely offset tangs 34 are provided on the top edge of the contact 26a. The tangs 34 may easily be formed on a rectangular contact member by a simple, well known mechanical process, such as lancing. In general, the circuit breaker, such as 28, is electrically connected to a bus bar such as 16, by the engagement of a socket clip such as 32 with the contact 26a. The socket clip 32 is contained within a recess in the circuit breaker 28.

FIGURE 3 shows a first type of clip 32 which is able 3 to engage the contact 26a. The clip 32, which is substantially U-shaped, has two resiliently connected leg portions'36, 38. The leg portion 38 which is on the same side as the protruding tang 34 is notched so as to have a cut away portion 40 extending almost the entire length of the leg 38.

FIGURE 4 shows the reception of the circuit breaker 28 having the first type of clip 32 onto the contact 26a. The circuit breaker is first positioned so that the recess 29 engages one of the hooks 30 on the support pan. The breaker is then pivoted about the hooked-on end so that the clip 32 of the circuit breaker is fully inserted on the contact 26a. The support hooks 30 are positioned so that each circuit breaker engages only one half of each contact. Due to the cut away portion 40, the tang 34 does not abut the clip, at least until it is fully received, the unnotched, rounded portions of the clip legs first resiliently engaging the contact 26a. Another breaker similar to breaker 28 may then engage the other half of the contact 26a in a similar manner.

In FIGURE 5 a second type of socket clip 42 is shown. This type of clip cannot engage the segregating contact 26a. The general shape of the clip 42 is similar to that of the first type of clip 32, the clip 42 also having two resiliently connected leg portions 44, 46. The leg portion 46 on the same side as the tang 34 is notched so as to provide a relatively shallow cutaway portion extending a short distance from the end of the leg 46. The cut away portion 48 forms a substantially horizontal edge 50 which extends part of the width of the leg 46.

In FIGURE 6 the attempted engagement of the clip 42 which is contained within a circuit breaker 52, is shown. The breaker is first pivoted about the recessed end, as described above. But it can readily be seen that the tang 34 of the contact 2611 abuts the horizontal edge 50 before the clip 42 can be substantially engaged onto the contact 26a. No reasonable amount of force on the circuit breaker 52 will allow the clip 42 to be fully received by the contact 26a.

If it is desirable that all types of circuit breakers can engage a contact, a substantially rectangular, universal contact 26b, as shown in FIGURE 7, can be provided. Therefore as shown in FIGURES 8 and 9, either the first type of clip 32 or the second type of clip 42 can engage the universal contact 26b without any impediment to the engagement as in either case, the rounded portion of the clip legs will first engage the contact 26b.

Therefore where it is desirable to have only certain types of circuit breakers capable of engaging a contact, the segregating contact 26a with tangs can be employed. The circuit breakers having the first type of socket clip 32 with a large notch can engage 26a, whereas those circuit breakers having a second type of clip 42 with a shallow notch, will abut the tangs and hence be rejected by the contact 26a. Thus a circuit breaker panel board segregation system is shown which is obtained through an inexpensive modification of common contacts and socket clips.

While I have disclosed only one embodiment of my invention, it will be apparent to those skilled in the art that many modifications thereof may be made and I, therefore, intend by the appended claims to cover all such modifications as fall within the true spirit and scope of my invention.

What I claim as new and desire to secure by Letters Patent of the United States is:

5 1. In a circuit breaker panel board comprising a support means; a plurality of circuit breakers, each pivotally engageable at one end to said support means; and a plurality of blade-like contacts which are supported at one end by said support means and are each electrically connected to one of a plurality of bus bars coming from an A-C power supply, the improvement comprising:

(a) at least one of said contacts having a lateral protrusion on the unsupported end thereof;

(b) at least one of said circuit breakers having at the other end thereof a contact engaging clip having a shallow notch therein, said shallow notch being of a depth and length such that it will abut the protrusion on said one contact to prevent complete engagement of said clip having said shallow notch and said one contact.

2. In a circuit breaker panel board as in claim 1, the

improvement further comprising: 7

(a) the other of said circuit breakers having at the other end thereof a contact engaging clip with a relatively large notch, said large notch being of a depth and length such that it will clear the protrusion on said one contact to allow complete engagement of said clip having said large notch and said one contact.

3. In a circuit breaker panel board as in claim 2, the

improvement further comprising:

(a) said one of said contacts having two lateral protrusions therefrom which are each located at a given distance in from opposite corners on an edge outward from said support means, the protrusions extending laterally on opposite sides of said one of said contacts;

(b) said support means comprising a circuit breaker engageable portion, said engageable portion positioned such that each of said circuit breakers, when pivotally engaged at the one end to said engageable portion of said support means, extends only to a distance halfway along the length of a corresponding one of said contacts.

45 4. In a circuit breaker panel board as in claim 3, the

improvement further comprising:

(a) the remainder of said contacts being substantially planar contacts;

(b) the length of said small notch and the length of said large notch being such that unnotched portions of any of said clips will first resiliently engage said planar contacts to allow complete engagement of any of said clips and said planar contacts.

References Cited UNITED STATES PATENTS 3,150,290 9/1964 Edmunds 317119 LEWIS H. MYERS, Primary Examiner. J. R. SCOTT, Assistant Examiner, 

